Galvalume steel coil, often abbreviated as GL Coil, is a next-generation coated steel product that combines the protective power of zinc with the durability of aluminum. The surface of the steel is coated with a mixture of approximately 55% aluminum, 43.5% zinc, and 1.5% silicon, which creates a unique balance of corrosion resistance, heat stability, and long-term durability.
Unlike traditional galvanized steel, Galvalume is designed for environments where moisture, salt, or extreme temperatures threaten the lifespan of regular materials. Because of its superior qualities, it has become the preferred choice for roofing, cladding, appliances, and industrial projects worldwide.
What makes Galvalume stand out compared to standard galvanized steel?
Exceptional Corrosion Resistance
The aluminum in the coating forms a barrier that prevents corrosion from spreading, while zinc provides sacrificial protection at cut edges. Consequently, Galvalume lasts two to three times longer than conventional galvanized steel in harsh outdoor conditions.
Superior Heat Resistance
The alloy coating remains stable under continuous exposure to high temperatures, often up to 315°C (600°F). Therefore, it is widely used in applications where thermal stability is critical.
Self-Healing Edges
When the surface is cut, zinc in the coating helps protect exposed steel, slowing down the spread of rust. This unique self-healing property adds to its reliability in construction.
Smooth and Attractive Finish
Galvalume coils feature a characteristic spangle or matte appearance that can be further customized. This not only improves aesthetics but also eliminates the need for additional painting in some cases.
Long-Term Cost Savings
Although the initial cost is slightly higher than galvanized steel, Galvalume reduces replacement, repair, and maintenance costs significantly, making it more economical in the long run.
Standards: ASTM A792M/EN10375, JIS G3321
Grades: DX51D, DX52D, DX53D, DX54D, S250GD, S280GD, S320GD, S350GD, S550GD
Coating Weight: AZ30 – AZ150 (grams per square meter)
Thickness: 0.12 – 2.5 mm
Width: 750 – 1250 mm (customizable)
Spangle Options: Regular, Minimum, Large, or Zero Spangle
Surface Treatment: Chromated, Passivated, Oiled/Non-oiled, AFP (Anti-Fingerprint)
Hardness Levels: Soft, Half-hard, Full-hard
Galvalume is one of the most widely used roofing and cladding materials in modern construction. Builders choose it for residential, commercial, and industrial roofing sheets, wall cladding, and prefabricated structures. Its long lifespan and minimal maintenance make it the first choice for airports, warehouses, and shopping complexes.
The automotive industry uses Galvalume for body panels, exhaust systems, fuel tanks, and heat shields because of its high-temperature resistance. In addition, its lightweight but durable structure contributes to vehicle efficiency.
Manufacturers of refrigerators, ovens, washing machines, and microwaves prefer Galvalume for its clean finish, rust resistance, and heat stability. The anti-fingerprint (AFP) surface treatment further improves its appeal in consumer products.
Traditional galvanized steel corrodes quickly in salty, humid coastal areas. However, Galvalume withstands these conditions remarkably well. Therefore, it is frequently used in beachfront construction, fishing facilities, and port warehouses.
Farmers and agricultural businesses rely on Galvalume for grain silos, barns, poultry houses, and greenhouse structures. Similarly, food processing and cold storage facilities prefer it due to its hygienic properties and durability.
Two to three times longer lifespan in outdoor and marine environments.
Better heat resistance, making it suitable for both construction and automotive industries.
Cost efficiency in the long term because maintenance and replacement costs are reduced.
Environmentally friendly, since Galvalume is fully recyclable.
Improved aesthetics with smoother finishes and optional coatings.
Finding the right supplier is as important as choosing the right product. By working with trusted suppliers such as Basekim, clients ensure consistency in coating weight, thickness, and surface treatment. Moreover, Basekim’s expertise in international standards and logistics guarantees reliable deliveries for both domestic and export markets.
Galvalume can last up to 40–60 years in non-marine environments and around 20–30 years in coastal areas, depending on the coating thickness and maintenance.
Galvanized steel uses only zinc, while Galvalume combines aluminum, zinc, and silicon. As a result, Galvalume provides much stronger corrosion resistance and heat stability.
Yes. Although Galvalume has a natural bright and attractive surface, it can be painted or laminated for decorative purposes. Painted Galvalume is widely used in architectural panels.
Construction, automotive, appliances, agriculture, and coastal infrastructure are the top consumers.
In many construction and roofing applications, Galvalume provides a more cost-effective solution than stainless steel, while still offering excellent corrosion resistance.